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subject: Contact Lenses - Which Type is Best for Your Eyes? [print this page]


Contact Lenses - Which Type is Best for Your Eyes?

At this point in time, more than 24 million people in the United States wear contact lenses of one type or another. Contact lenses offer a safe and effective alternative to eyeglasses; and have the ability to correct many vision problems through proper care and use.Many types of contact lenses are available. The type of contacts you use depends on your particular situation. Your eye doctor will be able to help you choose from the many types of lenses. "Hard" contacts, aka PMMA (polymethyl methacrylate), were the first lenses ever created. This type of lens has been around since the 1960's; but has some drawbacks that may limit their usage. The plastic used in hard lenses is durable, but does not allow oxygen to reach the cornea. While hard lenses served a purpose at one point in time, they are not as widely used today because this is the least comfortable type of lens to wear. There are people who still prefer to wear this type; mainly due to their durability and lower cost.Gas-permeable lenses are also known as "RGPs." This type of lens still falls in the "hard" category, but the plastics are combined with other materials such as silicone and fluoropolymers. These materials allow oxygen to pass directly through the lens. This is why they are called "gas permeable." Soft contact lenses, which are very popular today, are made of plastic materials that incorporate water into their composition. It is the water that makes this type of lens soft and flexible. The water is also responsible for allowing oxygen to reach the cornea.Within the category of soft contact lenses are: extended wear lenses, toric lenses and daily contact lenses. The differences between the three are:- Extended wear lenses are made of materials that allow the lenses to last 2 - 4 weeks.- Daily lenses are popular because they carry a lower risk of infection. However, this is one of the more expensive types of contact lenses.- Toric lenses are available in both rigid and soft materials. This is the type of contact lens used to correct moderate astigmatism. - It is important to remove contacts at bedtime in order to reduce the risk of infection and the risk of contact lens intolerance.Most people who need vision correction can benefit from wearing contact lenses, but there are some instances where contacts do not work well. Individuals who have frequent eye infections, severe allergies, or dry eyes (improper tear film) may find it difficult to wear any type of contact lens. Even daily contact lenses could prove difficult for individuals who work in environments that are dirty or dusty. Also people who may not have the skills to handle and care for the lenses properly, such as children, may not be the right candidates for contact lenses.When deciding if this is the right type of vision care solution for you or a family member; and to determine the best type for your particular situation; your best advice will come from your eye doctor.




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